I know i have posted this very late and I am sorry. I created a basic app that turns on an LED when i click an on button and turns it off when i click off, i did this using an arduino UNO board. the code is working perfectly even the bluetooth module is fine, but when i try to do it through my app, it always shows error 507, unable to connect, is the device turned on? A.I says its because of the android 12+ security problems and i dont know how to fix this. Please help me.
Thank you,
Akshaj Rarhi
Dear @Akshaj_Rarhi, I'm a bit confused in reading your post:
when you say "the code is working perfectly even the bluetooth module is fine," do you mean the Arduino code (I guess) ? And how do you can say that the BT module is working fine, when the error 507 is issued ?
Plase take a look to all the posts related to the permissions granting by searching the forum (tag "permission"). There are many solved posts related to the BT communication.
Other questions are: is your BT module a "classic module" HC06 or HC05 or a BLE ? Have you already tried to communicate toward your UNO board by using the SerialBluetootTreminal app (free on playstore), just to be sure that the phone is capable to "speak" to the Uno ? Be careful that some "fake" HC05 aren't classic BT shields, but BLE instead.....it's a long story... 
@uskiara Yes, it is the Arduino code. By observing the Bluetooth module, we can also determine whether it is functioning properly and actively searching for connections. On the HC-05 module, the LED blinking twice per second indicates that the module is unpaired and currently looking for a connection.
I have also installed the Serial Bluetooth Terminal app, and it successfully connected to the HC-05 and was able to send signals. However, I am not sure whether my Bluetooth module is genuine or a clone. Could you please help me determine whether it is a genuine HC-05 module?
Thanking You.
Dear @Akshaj_Rarhi,
if you have already istalled the SerialBluetoothTerminal (SBT) app on your phone and it is working fine, you're in sight of the target !
First of all, according to the type of connection that the SBT is capable of doing, you can discriminate whether BLE or classic: therefore if the SBT works by selecting Classic, this means that the HC05 is a genuine one, on the opposite, if the SBT works by selecting BLE, this means that the HC05 is a "fake" one and it works with BLE. In this second case, you shall use a specific extension to make your app working (you can find here on the forum or directly here : https://community.appinventor.mit.edu/uploads/short-url/hGnF4b8UZmFHVSy383IHSConKcN.aix).
Anyway, upon what you say, it seems that is a classic one, then, what you most probably need is to allow the required permissions (BT and Geolocalization at Android level). To this purpose you shall dig the forum by tagging "BT" and "permissions": there are so many posts related to this specific problem. You can also find benefit by having a look to the web sites of @Taifun (puravidapps) or @TIMAI2 (metricrat), or @ChrisWard (professorcad) where you can find chunks of code or ready made apps, or the FAQ managed by @ABG ....best wishes
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